Still in shock from the jury’s verdict, I was led from the courthouse into a white van. A convict in another compartment was boasting of how he drove off and sold luxury motors: BMWs, Mercedes and the like. He used an electronic device to override their immobilisers. Unseen figures from other compartments called out questions: “How long does it take?” “What models does it work on?” “How can I get one?” I listened, intrigued. I’d never stolen anything and didn’t intend to. Then again it sounded so easy …

Welcome to Britain’s academy of crime. Who ever thought that a good way to make society more law-abiding would be to lock up all the criminals together, rent-free, with no responsibilities and little to do but practise theft and violence on one another, ready to resume for real when release day comes?

Prison is said to serve four purposes: punishment, deterrence, rehabilitation and maintaining public safety. Yet with reoffending rates at around 50%, many clearly emerge feeling unpunished, undeterred and unreformed, putting the public in fresh danger.

Strong family ties, a secure home and a steady job can help an ex-con to go straight. But imprisonment breaks up families and costs offenders their jobs and often their homes. No wonder so many return to crime.

Society increasingly recognises such concepts as the “right to a private or family life”. It’s enshrined in the European convention of human rights. Yet every year some 200,000 children has either their mother or father in prison at some point. The system ignores these children’s right to a family life. What is the long-term cost of this emotional harm? The financial cost is certainly high, with these broken families likely to be left on benefits on top of the £40,000-a-year cost of each prison place.

Prison is a 19th-century approach to tackling crime. The 21st century brings new solutions. Satellite tracking could make “house arrest” cheap and effective. Smart curfews could let single parent offenders out just twice a day for the school run, punishing and preventing reoffending while preserving family life.

For the few who will not comply or pose too great a risk, money saved by closing prisons could be used to convert remaining institutions into secure colleges of work campuses. Full-time education or properly paid employment would reform detainees in a way that today’s restricted prison regimes cannot.

As for me, I’d happily have a tracking chip implanted under my skin to enforce a round-the-clock curfew as the price for living with my family. I think society would be better off with me working from home and paying taxes, rather than putting my feet up in prison and learning new scams. Luxury car owners may agree.